Apparatus for compressing liquid metal.



Flex

Patented Jan. 14, 1913.

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B. GBRD'AU. APPARATUS FOR OOMPBESBING LIQUID METAL.

. APPLIOATIOI FILED AUG. 20, 1912.

- 1,050,-%. Patented Jan.14,1913.

-- 2 BKEET8-BHEBT fnmaqrs.era's or nus-stream, GERMANY.

I APPARATUS roa oomranssiive LIQUID METAL froin=7escaping, s0 that bubbles were necessaril formed and rendered the block orous," particularly in the upperpart. .laterj method consistingin forcing the liquid steel by means. of'a hydraulic pistonupward againsttliewalls ofan upwardly tapering inold presented the defect,that no uniform pressure could -.be exerted upon all partsof the block, since thepressure de ended upon the. inclinationof'the mold wa ls andiupon' the resistance-produ'ced by the friction on these walls, the'etfective pressure decreasing:

upward and becoming e ual to zero atx'the top. Anotherknown met od of'compressing liquid, metal by means oftwo hydraulic is tons bearing from above and-below against the metal, the lower piston'being at the same.

time adapted to press themold roper made in several parts inwardl by arcing them, upward. against incline stationary .zabut-5 ments, presented the defect, that the asesinclosed in the metal were prevented rom escaping,*s0 that in conse uence or this noi compact steel could be pro need. No lateral pressure could be actually-exerted upon the iquid steel, since the force acting u on the lower piston was completely balance by theforce acting upon the upper piston. A special known method of 'reducingthe formation of bubbles in the upper partof the blockf consisted in heating the top of the block by means of se arate devices for keeping the steclin its liquid stateafter'the casting, so,

as to enable the gases to escape. The effect ot-this'method, however, was restricted and rendered uncertain by the comparatively rapid-progress of the congelatioh: of.--:.the. parts of steel out of rea'chroftliejlieating medium. v I Y My invention," relates ito improvements in an apparatus for compressing. metal" blocks while still liquid,- whereby the s'aid defects are avoided.

Specification of Letters Pam... Application filed August 20, 1912. Serial No. 716,016.

1: I willino'w tion with" re erence to the accompanying Patented Jan. 14., 1913.

" The chief improvement consists in that .the metal block is simultaneously subjected to vertical and horizontal ressures, which pressures can be regulated independently of oneanother, so as to compress'the liquid metal from all sides excepting at the top, while permitting the gases to escape. Means are provided for keeping the upper part of the metal in a liquid state for a longer time by heating the same, so as to permit the sings to ascend and to separate from the metal.

-"=" Tlieappara'tus comprises a main hydraulic press with two coaxial pistons movable one within the other and one piston being ada ted -to horizontally compress the mold mace lIlI-SBVGltLl pieces, while the-other piston-is adapted to press the liquid metal upwardfiagainst the upwardly tapering wall parts o the mold.

The apparatus also comprises a subsidiary hydra'ulic, press adapted to operate the main "hydraulic press'for drivingtits two pistons upward, 'Y'while regulating valves are provided'foradjusting' thepressures of the two hydraulic pistons. independentlyof one another; jz-The mold iseont-ai'ned'in a movableretain'er. adapted to be wheeled over the ftwofpistonsof the main'hydraulic press and to enga'g'e under abutments.

roceed to describe my invendrawing, in which Figure 1 is a vertical longitudinal sectionthrough a main hydraulic press and a retainer with the mold embodying my invention on the line w-m in Fig. 2. Fig. 2

is a horizontal section through the line y-z in Fi 1 and shows also in. a plan view a subsit ia'ry' h draulic press for operating the'main'hy raulici rose and also a mechanisinforop'erating the subsidiary press, and Figs. 3fa'nd-4 are detailswhich will be referred to later on.

simil r; characters of reference refer to similar parts throughout the several views.

Ajdenotes amain hydraulic. press essentially'consisting of'a cylinder 1 and two eoaxial pistons 2 and 5 movable one within the other, {the outer -p1St0I1- 2- being tightened against the cylinder 1 b means of a suitable leather packin 4 and tie two pistons being tightened against one another by a leather packing-5. The cylinder 1' is shown as made in one with two opposite hooked stationary abatinentst3,to]aiid two 'railsj 7, (i fi 2). Uponlthe' tworails7', 7 four wheels"8 8 of a movable annularretainer 9 aremade-to roll,

andthe retainer 9 i s-piovided' withtwo opposite" outerfprojections 10, --1 0 a'dapted to. engage beneath the two abutmen'ts 6, 6 and also with two inner projections 11, 11 adapted to normally supportan outer supporting rim-'12. The inner piston 3 and theupper wid ened part of the outer piston 2 are made to normally extend upward to a point slightly lower; than the .upper surfaces of the two innerv projections 11, 11. The inner piston 3 is made to support an inner supporting. cylinder 13, which is open above and closed below. When the upper surfaces of the two coaxial pistons 2 and 3 are a little beneath the upper surfaces of the two inner projections 11, 11, the movable retainer 9 can-be wheeled over the two pistons 2 and;3 of the main hydraulic pressA and be shifted off over the two rails 7, 7. Where so .pre-

ferred, the retainers!) maybe armed-with.

mail,-as shown at '16.

The mold proper is shown to consist of several longitudinal pieces 14, 14 (Figs. 3 and .4): whichcan be moved togetherand apart:in radial directions and are adapted to slide on the upwardly tapering'in'side of the retainer 9. The lower ends of the pieces 14, 14' are reduced in; thickness in the radial direction and may be made to slide radiallyone second ring 15 supported by the outer supporting ringj12, the upper surface of the ring 15being made :either smooth or so reoessed as .to leave sufiicient playto the pieces 14, '14. .On the bottomof the'cyli'nder; 13 a spring of. any 'knownconstruction, for

ample a pair of superposed 'disk-springs-17,-=

may be d1s'posed,u-on which a cylinderfil8 guided in the supporting cylinder 13 is made to hear. The upper end of the cylinder 18 forms one part of the-bottom of the mold proper, while the other part of the bottom is a ring 19-surrounding the cylinder 18 and bearing on the. supporting cylinder 13. The mold pieces 14, 14 may be provided in their joint faces with grooves 23, 23, in which elastic-feathers 20, 20 and refractory material 21 may be placed for filling them up. Also the spaces between the several mold pieces 14, 14 and between them and the bottom ring 19-may be filled up with refrac tory material 22 as shown at Figs.'1-, 3 and 4, whereby the mold is closed on allsides except'at thetop. K,

.A subsidiaryhydraulic-press B: (Fig. 2)- maybe provided foroperating theimain hydraulic press A,;the' cylinder 24 Tofu the l former being connected with the -1 cylinder 1-' of the latter by means. of a suitable:tube 25' and a channel 26.1 -The' 1'plunger;v 27 t of -'the 1 subsidiary J pressgT--;B;}mayboactuated in any lmown gmann'en. :for example by nieans; of a screw-"spindle" 28 as "shown,-'Which""may 'be operated frorn aneleetromotor 29 by means 0 azsha'ft 30, a worm (not shown), a worm -wheel 31, a shaft 32, another worm 33 and a worm wheel 34' fastened on the screw-spindle 28. The twopistons 2 and 3 are to be actuated independently of one another, for which reason the inner piston 3 is made to extend through the bottom of the main cylinder land to work in a second chamber 35, where it is tightened by means of a suitable leather packing 35. The second chamber 35 is connected with the tube 25 by means of a tube 36 and a channel 37. Two regulating valves 38 and 39 of any known construction are inserted in the two tubes 25 and 36, so that with their aid the pressures upon the two coaxial pistons 2 and 3 can be varied at will.

- The molten metal is in any known manner cast into the mold described, while the retainer 9 may be directly above the main cylinder 1 ormay occupy any position on the two rails 7, 7, after which it is wheeled over the upper ends of the two coaxial pistons 2 and 3. Then the motor 29 is started for actuating the plunger 27. \Vhen assuming the inner piston 3 who alone driven upward, it Wlll by means ofthe parts 13 and 17 force the two bottom parts 18 and 19 against the lower surface of theliquid metal in'gthe outer piston 2.to be alone driven upward, it will bymeans of the two superposed-rings 12 and15 force the longitudinalmold 'pieces'14, 14 upward along the up- !wardly-tapering inside (on the ri ofathe retainer 9, whereby the several :moldjpieccs 14, 14 will be movedxtogether,

ht in Fig.

while the elastic feathers 20,. 20 ,are bent (Fig. 4) and the refractory material 21, 22

is laterally s ucezed out, so that the coni gealing liquic metal will be substantially horizontally compressed. It is now obvious,

that by suitably adjusting the pressures upon the two coaxial pistons 2 and 3 by means of thetwo regulating valves 38 and 39 and therewith adjusting the speeds of the two pistons 2 and 3 relatively to one another, alsoby simultaneously compressing the liquid metal vertically and horizontally, it is possible to more energetically and uniformly compress the congealing metal 40, than was hitherto possible.

I Where so preferred, the friction between the outside of the mold pieces 14, 14 and the inside of the retainer 9 may be reduced-by 'inserting rollers 41, 41-be'tween'these parts, as isshown in Figs. 1 and 2. These rollers .41,.'41-can be made to roll within suitable recesses42, 42 on inclined races for-moving togetherfthe. mold pieces 14, 14. I

In order to promote the formation of compaet' metal, alsoxany known heating device may be-exnploycd.-- F917 example an 'am'tular inverted burner 1'43 E attached] to agas supplying" tube 44: may be "in any known manner movcdover 'the mold pieces 14,- 1'4,so' that. after ignitingt-he gas the'fiames projecting from the burner 43- are directed downward on the top of the liquid"metal for maintaining the upper part of the cast metal in its 11 uid state. When after a comparatively siort time the slag in the metal has risen to the top, the gas can be tamed ottfor extinguishing the flames and then the heating device may be moved away from the moldu For the production of hollow metal blocks a suitable tool, such as for example a tapering punch 45 in Fig. 1, may be employed, whichcan be vertically moved and forced downward in any known manner through the liquid metal, say until its lower end strikes the cylinder 18 and may depress it against-the pressure of the springs 17 in the supporting cylinder 13. For example a suitable column 46 may be fastened on a projection 47 of the main cylinder 1 and may carry on its upper end a turnable frame 48, which can be swung 'by hand or in any known manner forimoving the punch 45 into and out of theaxis of the mold. The punch 45 may be connected with a vertical screw spindle ii), which. can be moved up and down in any known manner, for example by means of a. hand-wheel 50, a shaft 51 and bevel wheels 52 and 53. It will then be possible to move the punch 45 and also the heating device 43, 44: out of the way and to cast the liquid metal from some ladle above into the mold 14, 18, 19. Afterward the heating device i3, 44 is moved over the mold and the gas is turned on and-ignited, then the frame 4-8 is turned to move the punch 45 into the vertical axis of the mold after which the and to pierce tie liquid metal 40. \Vhen the slag and gases inthe metal have arisen and the gas for the heating device 43, 44 is turned off, the liquid metal can commence t'o congcal while being compressed and the punch 45 may be slowly withdrawn upward from the metal.

For removing the com ressed and congealed metal block from he mold, the two coaxial pistons 9. and 3 are caused to descend and the wheeled retainer 9 may be shifted to the side on the rails 7, 7, after which it may be in any known manner liftedtogether with the mold pieces 14, 14, so that the metal block is left behind on the bottom parts-18,19 and can be taken off.

\Vherc so preferred, the retainert). may

be divided into two coaxial parts, of which the inner part indicated by the dotted lines in Fig; '1 is cylindrical on the outside and is in any known manner connected with the unch 45 is made to descend mold pieces 14, 114-. Then it will be possible to withdraw upward the inner cylindrical part-together with the mold )ieces 14, 15 and the-cast meta-l block 40 or removing the latter.

The apparatus described can be varied in .many respects without departing from the s irit of my invention.

I c aim:

1. In an apparatus for compressin liquid metal, the combination with a vertical annular retainer having an inside tapering upward, of mold pieces vertically movable on the inside of said retainer and adapted to be jacked so as to form the mantle of a mold having an inside tapering upward, a bottom adapted-to be packed in said mold mantle, a hydraulic press cylinder adapted to be connected with the lower end of said retainer, two coaxial pistons in said hydraulic'press cylinder, the inner piston being'adapted to act upon said bottom and the outer piston to act upon said mold pieces, and means for forcing said two pistons upward.

2. In an apparatus for compressing liquid metal, the combination with a vertical annular retainer having an inside tapering upward, of mold pieces vertically movable on the inside of said retainer and adapted to be acked so as to form the mantle of a mold iiaving an inside tapering upward, a bottom adapted to be packed in said mold mantle, a hydraulic press cylinder adapted to be connected with the lower end of said retainer and havin two separate coaxial chambers, two coaxial pistons movable one within'the other and working severally in "the two chambers of said hydraulic press cylinder, the inner piston being adapted to act upon said bot-tom and the outer piston to act upon said mold )ieces, and means for separately forcing sai two pistons upward from said hydraulic press cylinder.

3. 'In an apparatus for compressing liquid metal, the combination with a vertical annular retainer having an inside tapering upward, of mold pieces vertically movable on the inside of said retainer and adapted to be packed so as to form the mantle of a mold raving an inside tapering upward, a bottom adapted to be packed in said mold mantle, a hydraulic press cylinder adapted to be connected with the lower end of said retainer, two coaxial pistons movable one within the other in said hydraulic press cylinder, the inner piston being adapted to act upon said bottom and the outer piston to act upon said mold pieces, means for forcing said two pistons'upward from said hydraulic press cylinder, and a heating device adapted to be moved over the mold for heating the top of the liquid metal.

4. In an apparatus for compressing liquid metal, the combination with a vertical an- -n 'u1 a r etainer havin g, an nside tapering ..ward,- of "moldipieces verticallyimovab e.. on the-inside of saidretainer' and adaptedto be packed so as jit-o -form-the mantle of a fin'old iaving. an inside taperingupwa rd,' a* bottom adaptedstobe paekedr in sa d: mold mantle','-'

- mold .within t ajhydra'ulic f-..-pressf: cylinder"? adapted; to be connected wit 1 twofcoaxial pistons movable one .within the other "and working severally in the; two

chambers, of said v-i-hydraulic :press' eylinder,'.

.ing adapted to act upon said bottom and the the inner piston being adapted toae't; upon said bottom and:the. outer"p1ston to act upon said moldpiecesQhmans for. 'se' arately'-'forc-- ingh said" two pistons upward roms'aid .,hy-'

i draulielpress flcylinder, iand'a heating ,device ladaptedato.1'be; movedover-{the ,mold for heatingethetoploftheliquidjmetal.

';5:;-In' an'i' 'pparatus' 'for compressing liquid metal, a the combination with a .-vert1cal,-' an nular, I retainer having"; an.,. inside tapering upward,-"; of -mold piec es. vertically .jmovable o 1 i,;the 1i1side,'oflsaidg retainer';and l'adapted to1-1be {packed so ras to: form the mantle of a seminar two, "coaxial; is'tons, movable one he other in s'ai hydraulic press cylinder,"ithe inner piston belng ada ted to actupon said'bottom anid the outer' plston" mace; uponesaidmolda -pie'ces,:f. means= for forcing -said two pist0nsji1pward l'from said?- hy-- idraulic press cylinder,-Jja" punch-adapted to:-

pierce ,from' above :the" liquidijmetal I in l the m'old,-means qfor vmoving said' puneh into,

I and-out, of the ;.axi s of a said retainer, and{ means: for vertically moving said punch j' '16. .-.In an apparatus for;cempressing liquid nietalpthe' combinationi'with' vertical an nular'retainer having an inside taperm up-v ward, of. mold pieces ,vertieally movab e on the. inside of said retainer and adapted to be packed so'as to form the mantle of a mold having an inside tapering u ward, abottom adapted to be packed insai mold mantle, a"

hydraulic; ress cylinder adapted to be connected ,wit 1 the lower end of said retainer and havin a two. separate coaxial, chambers, two coaxia PlStOIlS- IDOVflblOOHB within the other and working severally inthe two chambers of said hydraulic presspcylinder, the innerpiston being adapted to act'upon;

said bottom; and the outerpiston to act upon said moldpieces,'imeansforase arately tore;

ing 's'aidrtwfo pistons upward; rom said -hydraulie 'press. cylinder, a;,punch ;adapted=- to pierce above} the liquid; metal {infithe im nsr' e msrs ,see-P mam -i outyof,tlie'j'axisr'ofism f retamer aan meansamev asi i ypu t.

anularfretainer having an in'sidetapering wardiand recessesw th lnclined tlieflowe'rjendof-said retaineru and hav ng; two separate coaxial chambers,"

aving an f insideig-ta ering upward, a 'bottomadaptedto beipac ed ,in said mold r mantle',i-,.a; hydraulic f-press cylinder adapted: to};befconneeted={witln the lower end-of said this" insid I of f rollers Am J the recesses, of said retaineremoldi pieces "vertically movable 1 on 'saidi rollersand adaptedto be packed soas to, ;form' a.mantle-of amoldhaving an inside. .taperingZ-"upward, a bottom adapted to be fl-packeds in'isaidlmold mantle, a hydraulic 'press cylinder adapted'to be connected with thelowerj-end of said retainer, two coaxial plstons movable one within the other in said ydraullc press eyllnder, the inner piston beouter' piston to act upon said mold pieces,

and means for forcing said two pistons upward from said hydraulic press cylinder.

. 8.:In an apparatus for compressing liquid metal, the combination with a vertlcal annular. retamerrhavmg an 1ns1de tapering upward and recesses with inclined bottoms in this inside, of rollers in the recesses of said retainer, mold pleces verticall movable on said rollersandadaptedto e )acked so as to form the mantle of a mold having an insideta ering upward, a bottom adapted to be pacliedin said mold mantle, a hydraulie" press cylinder adapted to be connected -.-with the lower end of said retainer and hav- =ingtwo separate coaxial chambers, two co- ,axlal pistons movable-one within the other and-working severally in the two chambers of said "hydraulic press cylinder, the inner :pistonbeing-adapted to act upon said bot- :tom and the outer piston to act'upon said moldfpiece's, and means for se arately-foreingSaidtwdpisto'ns upward rom said hy- ,draiilic press cylinder.

19. In an apparatus for-compressing liquid imetal, the combination .witha: vertical an- ;nularf retainer having an inside tapering. upward and recesses with-inclined bottoms int-hisin'side, of rollers in the recesses of said retainer, mold pieces vertically movable on said rollers. and adapted to be packed so ,as

to form the mantle of a mold having an invside tapering upward, a bottom adapted to be paekedin-said mold mantle, a hydraulic presscylinder adapted to be connected with the lower end of said retainer, two coaxial pistons movable one within the other in said hydraulic press cylinder, the inner piston being adapted to act upon said bottom and the outer piston to act upon said mold pieces, means for forcing said two pistons upward from said hydraulic press cylinder, and a'heating-devicc adapted to be moved ever the ,mold for heating the top of the liquid metal;- v i- "'l0.-.In-E ,anapparatus for compressing liquid netal', the.'combination with a vertical-annular retainer. having an inside tape'ring. upward" andzrecesseswith, inclined 'bottomsun this inside, ofirollers in the rea s u d m'eta1,-. theicombinationtwltha vertical an cesses';-,of} saidretainer, mold' pieces vertically movable .on sald rollers and 4 adapted ottomsm v.., fm'ol h'jvingL'a'n 'inside; tapering, upward, .ibottom"; adapted to be "packed in -.g said mold mantlef-ral hydraulic :press cylinder adaptedltofbe connected; with the lower end 1 'ofIsaid-* retainer and" having two separate coaxial chambers two coaxialpistons movable onewithin the other-andworking severally.1;,in":-'the'jjftwo chambers of 'said hying"' adap te'd to' actjupon said bottom and the; outer? piston toact-iuaon said mold pieces, means for. separate y'fOrcinE said two'v pistons upward from said by raulic jpress'cylinder, and a heating device adapted to be moved over the mold for heating the top of the liquid metal.

11. In an apparatus for compressing liquid metal, the combination with a vertical' annular'retainer having an inside ta-' citing-upward and recesses with inclined ottoms in this inside, of rollers in thereically; movable on said rollers and adapted tobe acked-so as to form the mantle of a mol having an inside tapering upward, a; bottom.. adapted to be packed .in said mold =mantle, a hydraulic press. cylinder adapted'tobeiconnected with the lower end ofsaid retainer,'two coaxial pistons mov able'one vwithin the-other-fin' said hydraulic' press cylinder, the; inner piston being adapted to act'upon said bottom and the outer piston to act upon said mold pieces, means for forcing said two pistons upward from said hydraulic tpress cylinder, a punch adapted to pierce r liquid metal in the mold, means for moving said punch into and outof the axis of fldraulic pressfcylinder, the inner piston be-.

cesses-{of said retainer, mold pieces 'ver-- ward from said iydraulic a punch adapted to pierce om above the 7 i said retainer, and means for vertically moving said punch.

; l2. an apparatus for compressing liquid metal, the combination with a vertical annular retainer having an inside taperingupward and recesses with inclined bottom'sin this inside, of rollers in the recesses of said retainer, mold pieces vertically movable on said rollers and adapted to be acked so as to form the mantle of a moldjiiaving an inside tapering upward, a bottom adapted to be packed in said mold mantle, a hydraulic press cylinder adapted to be connected with the lower end of said retainer and having two separate coaxial chambers, two coaxial pistons movable one within the other and working severally in the two chambers of said hydraulic press cylinder, the inner piston being adapted to act upon said bottom and the outer piston to act upon said mold pieces, means for separately forcin said two pistons upfpress cylinder, rom above the liquid metal in the mold, means for moving said punch into and out of the axis of said retainer, and means for vertically moviug said punch. i

13. In an apparatus for compressing liquid metal, the combination of a mold com osed of a plurality of spaced sections having coves at'their opposed faceswith elastic eathers engaging said grooves, and a refractory filling interposed between the sections.

BARTHOLD GERDAU. [L. s.]

\Vitnesses: HELEN NUFER, ALBERT NUFER.

Oopiu oi this patent maybe obtained tor iive cents each, by addressing the Commissioner of Patents,

Washington, D, 0. 

